Mitral and tricuspid valve replacement and repair are traditionally performed with suture techniques. During valve replacement, sutures are spaced around the annulus (the point where the valve leaflet attaches to the heart) and then the sutures are attached to a prosthetic valve. The valve is lowered into position and when the sutures are tied, the valve is fastened to the annulus. The surgeon may remove all or part of the valve leaflets before inserting the prosthetic valve. In valve repair, a diseased valve is left in situ and surgical procedures are performed to restore its function.
Frequently, an annuloplasty ring is used to reduce the size of the annulus. The ring serves to reduce the diameter of the annulus by allowing the leaflets to oppose each other normally and prevent re-dilation of the annulus. Sutures are used to attach a prosthetic ring to the annulus and to assist in plicating the annulus. This procedure, like heart valve replacement, is time-consuming. If the ring is severely malpositioned, then the stitches must be removed and the ring repositioned relative to the valve annulus during restitching. In other cases, a less than optimum annuloplasty may be tolerated by the surgeon rather than lengthening the time of surgery to restitch the ring.